PROJECT SUMMARY/ABSTRACT: I, Edward R. Marcantonio, MD, SM, am a board-certified geriatrician and patient-oriented aging researcher, Associate Professor of Medicine at Harvard Medical School (HMS) and Director of Research in the Division of General Medicine and Primary Care at Beth Israel Deaconess Medical Center (BIDMC). The long term objectives of my career are to conduct patient-oriented research (POR) to improve the quality of care and outcomes of hospitalized older adults, and to provide mentoring to new investigators interested in POR in aging. Over the past 16 years, I have built a successful, independent, NIH-funded program of research focused on delirium (acute confusion), a common, morbid and costly condition in hospitalized older adults. I have conducted a series of observational and interventional studies designed to improve diagnosis, target individuals at risk, identify modifiable risk factors, and test intervention strategies to reduce the incidence, severity and duration of delirium. Through these studies, I have gained the knowledge and skills necessary to conduct high quality POR and to mentor new investigators, and have been recognized for my excellence in mentoring with two prestigious awards. In this context, the primary objectives of this K24 Award are: 1. To continue to build a research program around improving the quality and outcomes of care for hospitalized older adults with delirium. This objective will be accomplished through my currently funded studies, including an NIA-funded R01 entitled 3D-CAM: Deriving and validating a 3-Minute Diagnostic Assessment for Delirium, and my new research, a Biomarker Discovery for Delirium project described in this application. Receipt of the K24 will enable me to more effectively leverage these studies and other ongoing work to support the work of trainees, who will in turn expand my research program. 2. To build a mentorship program that will expand POR in aging at BIDMC and HMS, with a focus on delirium and related conditions. This objective will be accomplished through structured, individual mentorship of young investigators with a strong interest in POR. Protected time for mentorship will be provided by the K24 award. 3. To expand my mentorship program to include translational, interdisciplinary work around biomarker discovery for delirium, and biomarker applications to improve risk stratification, diagnosis, and prognostication of older adults with delirium. This objective will be accomplished through my new research project, career development activities, and interdisciplinary collaborations that will be facilitated by receipt of the K24 award. My objectives will be greatly facilitated by the superb academic environment and outstanding institutional support provided by HMS and the BIDMC Divisions of General Medicine and Gerontology.